Affiliation:
1. Shandong University
2. Purple Mountain Laboratories
3. Beijing Academy of Quantum Information Sciences
4. Frontier Science Center for Quantum Information
5. Beijing National Research Center for Information Science and Technology
Abstract
Whispering-gallery-mode (WGM) microcavities have shown significant applications in nanoparticle sensing for environmental monitoring and biological analysis. However, the enhancement of detection resolution often calls for active cavities or elaborate structural designs, leading to an increase of fabrication complexity and cost. Herein, heterodyne amplification is implemented in WGM microsensors based on backscattering detection mechanism. By interfering with an exotic reference laser, the reflecting light backscattered by perturbation targets can be strongly enlarged, yielding an easy-to-resolve and consequently sensitive microsensor. The dependence of detection laser frequency has also been characterized with the assistance of optothermal dynamics. We show that exploiting heterodyne interferometry boosts the detection of weak signals in microresonator systems and provides a fertile ground for optical microsensor development.
Funder
National Natural Science Foundation of China
National Key Research and Development Program of China
Special Project for Research and Development in Key areas of Guangdong Province
Natural Science Foundation of Shandong Province
Beijing Innovation Center for Future Chip
Tsinghua University Initiative Scientific Research Program
Subject
Atomic and Molecular Physics, and Optics